Number density of the visible γ-ray pulsars obtained for each model as a function of α and ζ in the population synthesis of Pierbattista et al. (2012). The linear grey scale saturates at 1.5 star/bin. The pink contours outline the density obtained for the radio-loud γ-ray sub-sample (at 5% and 50% of the maximum density). The insert gives the set of ζ values measured by Ng & Romani (2008) from the orientation of the wind torus seen in X rays (pink lines) and by Caraveo et al. (2003) from the orientation of the Geminga X-ray tails (green line). The separation in α in the insert is meaningless.